GB2412417A

GB2412417A - An expansion bolt

Info

Publication number: GB2412417A
Application number: GB0407001A
Authority: GB
Inventors: Pan-Ching Huang
Original assignee: Joker Industrial Co Ltd
Current assignee: Joker Industrial Co Ltd
Priority date: 2004-03-27
Filing date: 2004-03-27
Publication date: 2005-09-28
Anticipated expiration: 2024-03-27
Also published as: GB2412417B; GB0407001D0

Abstract

An expansion bolt comprises a bolt 31, an expanding sleeve 32, and a conical nut 33. The expanding sleeve comprises expanding sections 324 325, an end section 321 and a stop 323. Expansion of the sleeve is caused by compression due to movement of the conical nut along the bolt. The stop 323 limits the movement of the nut relative to the sleeve and enables complete radial expansion to be achieved. The stop is a strip section formed integrally of the sleeve which is bent inwards by stamping. The end section 321 of the sleeve has a slot 322.

Description

EXPANSION BOLT ASSEMBLY CAPABLE OF

PREVENTING INCOMPLETE EXPANSION

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an expansion bolt assembly capable of preventing incomplete expansion to achieve a desired expansion effect when the action section of a nail tube is compressed to accomplish secured fastening in construction hole.

2. Description of the Prior Art

Expansion bolt assembly is used to hang articles on a wall or to serve coupling function. As the wall generally can be divided into solid wall and hollow wall, the expansion bolt assembly also has two types to suit different types of walls. FIG. 1 illustrates a solid wall W1 and an expansion bolt assembly 1 used thereon. The expansion bolt assembly 1 includes a bolt 11, a nail tube 12 and a conical nut 13. During construction the expansion bolt assembly 1 is inserted into a construction hole D1, then the bolt 11 is turned to move the conical nut 13 at other end to compress the receiving section 121 of the nail tube 12 and expand the receiving section 121 to wedge in the construction hole D1. FIG. 2 illustrates a hollow wall W2 and the expansion bolt assembly 2 used thereon. The nail tube 2 has at least one or more action sections 222 and 223 behind the receiving section 221 of the nail tube 22.

During construction the expansion bolt assembly 2 is inserted into a construction hole D2, then the bolt 21 is turned to move the conical nut 23 at other end to compress the receiving section 221. The expanded spot of the receiving section 221 may not be located in the solid portion of construction hole D2. When the bolt 21 is turned continuously and generates the compression force, the conical nut 23 might be trapped in a lower portion of the receiving section 221. When the compression force increases, the action sections 222 and 223 will receive the compression force and be deformed and expand. As long as the receiving section 221 or the action sections 222 and 223 have one expanded spot to wedge in the construction hole D2, the nail tube 22 may be fastened. However, in practice, the conical nuts 13 and 23 often cannot withstand the compression force and moves excessively lower, and escapes the receiving sections 121 and 221. As a result, the expansion process is not fully carried out and the expansion is incomplete, and construction defect occurs

SUMMARY OF THE INVENTION

In view of the aforesaid disadvantages, the primary object of the invention is to provide an expansion bolt assembly capable of preventing incomplete expansion. The expansion bolt assembly according to the invention has a stamped transverse strip section on a lower side of the receiving section of the nail tube. The strip section is bent inwards to form a semi-circular retaining blade abutting the inner wall of the nail tube. The original location of the strip section forms an opening. The retaining blade can stop the conical nut from moving downwards excessively when the receiving section is compressed so that the action section of the nail tube may be fully expanded to achieve secured fastening in the construction hole.

The foregoing, as well as additional objects, features and advantages of the invention will be more readily apparent from the following detailed description, which proceeds with reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG.1 is a sectional view of a conventional expansion bolt assembly used on a solid wall.

FIG.2 is a sectional view of a conventional expansion bolt assembly used on a hollow wall.

FIG. 3 is a perspective view of the invention.

FIG. 4 is an exploded view of the invention.

FIG. 5 is a flattened view of the nail tube of the invention.

FIG. 6 is a cross section taken on line I-I in FIG. 4 after bent and formed.

FIG. 7 is a schematic view of the invention used in a hollow wall in an operating condition -1.

FIG. 8 is a schematic view of the invention used in a hollow wall in an operating condition -2.

FIG. 9 is an exploded view of another embodiment of the invention.

FIG. 10 is a schematic view of another embodiment of the invention used in a solid wall.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 3 and 4, the expansion bolt assembly 3 according to the invention includes a bolt 31, a nail tube 32 and a conical nut 33. FIG. 5 illustrates the flatten view of the nail tube 32. The conical nut 33 has a conical upper section 331 and a lower section with one or more rib 333 formed on the periphery. The nut 33 has a screw hole 332 to couple with the thread section 311 of the bolt 31. The nail tube 32 has a receiving section 321 on one end to receive the conical nut 33 by compression. The receiving section 321 has one or more slot 322 to couple with the rib 333 of the conical nut 33. The slot 322 can restrict the moving direction of the conical nut 33. The receiving section 321 has a stamped transverse strip section 323 on a lower side. The strip section 323 is bent inwards to form a semi- circular retaining blade 323' abutting the inner wall C of the nail tube. The original location of the strip section 323 forms an opening 323" (referring to FIG. 6). The retaining blade 323' can prevent the conical but 33 from moving excessively lower during compressing the receiving section 321. The lower side of the retaining blade 323' is abutting one or more action sections 324 and 325. Each of the action sections 324 and 325 has a plurality of slots 324' and 325' spaced by corresponding rib blades 324" and 325". The slots 324' and 325' have the greatest width in the middle portion (while the middle portion of the corresponding rib blades 324" and 325" are the narrowest) and two tapered ends so that the middle portion is weakest during compression and may be deformed first and expanded outside. The action sections 324 and 325 are formed for the hollow wall.

The main feature of the invention is the transverse strip section 323 at the lower side of the receiving section 321 of the nail tube 32. The strip section 323 is bent inwards to form a retaining blade 323' to serve as the lowest point of the movement of the conical nut 33 during compression so that the receiving section 321 may be fully expanded and the conical nut 33 may be prevented from slipping into the action sections 324 and 325. Therefore the action sections 324 and 325 may be fully expanded to achieve desired construction quality.

Refer to FIGS. 4, 7 and 8 for an embodiment of the invention adopted on a hollow wall W3. First, the expansion bolt assembly 3 is sunk into a construction hole D3, and the bolt 31 is turned to compress the upper section 331 (conical s section) of the conical nut 33 into the receiving section 321. When the maximum expansion is reached, it arrives the retaining blade 323' and is stopped from moving forwards. Continuously turn the bolt 31 to compress the action sections 324 and 325. As the middle portion of the rib blades 324" and 325" is the weakest, deformation occurs on that portion and it is expanded outwards. During the entire expansion process, as long as one of the action sections 324 and 325 wedges in the inner wall of the construction hole D3, the nail tube 32 may be fastened tightly to the construction hole D3 (referring to FIG. 8).

Refer to FIGS. 9 and 10 for an embodiment of the invention adopted on a solid wall W4. First, the expansion bolt assembly 4 has a receiving section 421 at one end and a transverse strip section 423 located on a lower side of the receiving section 421, and a bolt 41 coupling with a conical nut 43. As previously discussed in the foregoing embodiment, the strip section 423 is bent inwards to form a semi-circular retaining blade 423' abutting the inner wall of the nail tube to serve as the lowest spot of the conical nut 43 during compression. The original location of the strip section 323 forms an opening 423". When the receiving section 421 is expanded outwards and the conical nut 43 reaches the retaining blade 423' and is stopped by the retaining blade 423' without moving forwards, the bolt 41 may be turned continuously to transfer the force to the action section 422. As the action section 422 has carved openings 422' and a weaker strength, the abutting portions 422" of the carved openings 422' will expand outwards under the compression to form a secondary expansion (referring to FIG. 10) so that the nail tube 42 of the expansion bolt 4 may be fully expanded in the construction hole D4 to achieve secured fastening.

In summary, the nail tube of the expansion bolt assembly of the invention can be fully expanded under compression to achieve secured fastening in the construction hole to overcome the problems occurred to the conventional expansion bolt assemblies.

Claims

I claim: 1. An expansion bolt assembly comprising a bolt, a conical nut

and a nail tube, wherein the nail tube has a receiving section which has a stamped transverse strip section on a lower side, the strip section being bent inwards to form a semi-circular retaining blade abutting the inner wall of the nail tube and an opening formed on the original location of the strip section.

2. The expansion bolt assembly of claim 1, wherein the receiving section of the nail tube has at least one slot.

3. The expansion bolt assembly of claim 1, wherein the nail tube has at least one action section abutting a lower edge of the retaining blade.

Amendments to the claims have been filed as follows 1. An expansion bolt assembly comprising: a bolt; a conical nut engageable with the bolt; and a sleeve including a receiving section adjacent a first end thereof, the receiving section including a retaining member lying adjacent an inner surface of the sleeve, the retaining member being formed from a stamped strip section of the sleeve, whereby the retaining member defines a continuous loop of a portion of lo the sleeve; the retaining member preventing movement of the conical nut relative to the sleeve.
2. An expansion bolt assembly according to Claim 1 wherein the receiving section further includes at least one slot.
3. An expansion bolt assembly according to Claim 1 or Claim 2 wherein the sleeve includes at least one action section adjacent to the retaining member, characterized in that said action section deforms and expands upon compression.
4. An expansion bolt assembly generally as herein described with reference to Figures 3 to 10 of the accompanying drawings. q